Modelling and optimization ofCandida rugosananobioconjugates catalysed synthesis of methyl oleate by response surface methodology

Abstract

Esters, such as methyl oleate, are functionally important compounds in many industrial sectors, mainly as components for manufacturing of emulsifiers, detergents, intermediate stabilizers and wetting agents. Acid functionalization of multiwalled carbon nanotubes (F-MWCNTs) by using a mixture of HNO 3 and H 2 SO 4 (1:3, v:v) was employed as the matrix for the adsorption of Candida rugosa lipase (CRL) as nanobioconjugates (CRL-MWCNTs) for the production of methyl oleate. Structural information of the developed CRL-MWCNTs was confirmed using Fourier Transform Infrared spectroscopy, thermogravimetric analysis and transmission electron microscopy, which revealed a successful attachment of CRL onto the F-MWCNTs. Process parameters (reaction time, temperature and alcohol:acid molar ratio) were optimized for high percent conversion of methyl oleate. Structural analysis established that CRL was successfully attached to the surface of the F-MWCNTs. Under the optimized conditions, which were 13.87 h, 51 C, molar ratio oleic acid: methanol (1:3.80), a high ester yield of 90.90% was attained. Also, under conditions of the shortest reaction time of 6 h, 47.07 C and acid:methanol ratio of 1:2.54, the CRL-MWCNTs catalysed a 74.51% ester yield. Hence, we established that response surface methodology (RSM) can be a practical technique for the prediction of the conditions that favour the high yield production of methyl oleate. Under optimized conditions, the CRL-MWCNTs nanobioconjugates are potentially good and economical biocatalysts for the production of methyl oleate, as well as other types of commercially important fatty-acid methyl esters.

Optimization of ethanolic transesterification ultrasound‐assisted from oil mixtures utilizing Box‐Behnken design

“…The coefficient of determination, R 2 , obtained for the model was .9780, explaining 97.80% of the variation in the mass yield of the mixture of castor oil and peanut oil in the production of biodiesel. The high value of the coefficient of determination confirms that the quadratic polynomial model was adequate to explain the relationship between the real response and the independent reaction variables, a similar finding verified in other studies with biodiesel optimization …”

“…The high value of the coefficient of determination confirms that the quadratic polynomial model was adequate to explain the relationship between the real response and the independent reaction variables, a similar finding verified in other studies with biodiesel optimization. 27,28 In this work, the model shown all linear terms, alcohol:oil ratio and catalyst amount as quadratic terms were significant. Cubic terms were important to describe significantly the model.…”

Synthesis of Ricinoleic Acid Estolides by the Esterification of Ricinoleic Acids Using Functional Acid Ionic Liquids as Catalysts

“…The minimum AV can be found in high temperatures 130 and high IL load 10 18 . And elliptical contours can be obtained between temperature with IL load, which indicated that the interaction of reaction temperature and IL load was very significant 24 . Figure 6B shows that, compared with reaction time, the effect of reaction temperature on the synthesis of RA estolides was more significant, which can also be found from Table 2.…”

Purification and characterization of dehalogenase from Bacillus cereus SN1 isolated from cow dung

“…In addition, Wahab et al, (2014) stated that the protein folds begin to unravel excessively when the optimum temperature of an enzyme has been exceeded. The reason for this kind of behavior is because the molecules (DehSN1 and 2,2DCP) tend to move faster when the temperature is raised, concomitant with the observed increase in rate of the DehSN1 reaction (Marzuki et al, 2015;Manan et al, 2016;Isah et al, 2017;Manan et al, 2018;) between the enzyme and the 2,2DCP molecules within the system. In contrast, the apparent low dehalogenase activity below 30 °C ( Figure 5) was presumably due to the DehSN1 dehalogenase protein structure being too rigid and unable to unfold into its catalytically active form to catalyze the degradation of 2,2DCP (Isah et al, 2017).…”